new radiator warm at top cold at bottom

[robgibson56]

Hi

I'm sorry if this question has already been asked but I couldn't see it on the forum.

I have recently had three new radiators fitted on the gound floor of my end of terrace house - two in the living room and one in the kitchen. Two out the three work great along with the other ones on the house.

However one of the ones in the living room is luke warm at the top and cold at the bottom. The pipe keading to the TRV is cold too. I have bled it, tapped the pin inside the new TRV which moves and most of the pipe which leads to the pump has been cleared. I have also tried to switch all the other radiators off and leave this one on but to no avail. It may not be relevant but the old radiator which was located there before did not work at all either but I believe that was really really old and had collapsed inside.

Please can anyone help?

 

[spacethegas]

i think you may be looking at a powerflush.

there may be other options but you will need advice from someone looking at job.

 

[DP]

There are plenty reasons why the original rad did not work.

1. It might have been plumbed in plastic which then blocked up if system is sedimented.

2. The pipe may be kinked which again (if system sedimented) might block up where the 'crimp' is.

3. Air lock.

4. If microbore, look at connections where larger bore feeds smaller bore.

Doubt if the rad would have collapsed internally. If that had indeed taken place, outside would have been paper thin and you would have had a leaking rad by now.

 

[robgibson56]

Thanks to both of you who have posted comments - very much appreciated. I am going to look at all the ideas and see if they work. Thanks again.

 

[hi1]

If the trv was fitted to the wrong pipe i.e outlet rather than inlet would this affect the flow through the rad? The heat you are getting is possibly from the return and hence colder and might not be hot enough to open the tvr to allow through flow.

 

[spacethegas]

If the trv was fitted to the wrong pipe i.e outlet rather than inlet would this affect the flow through the rad? The heat you are getting is possibly from the return and hence colder and might not be hot enough to open the tvr to allow through flow.

that is not the way trvs work. if the trv was single direction it would make no difference until it tried to shut down. note, old rad didn't work.[/u]

 

[doitall]

Blocked return pipe gets my vote

 

[robgibson56]

If it is a blocked return pipe would a power flush do the trick and is it a big job?

 

[twgas]

you have, I presume, checked the lockshield valve is open.

 

[robgibson56]

Yes I have checked this valve. Thanks for the suggestion.

 

[lagunaglen]

Does the pipework for this rad drop down from the floor above or is the pipework coming from below?

 

[robgibson56]

it's coming from the floor below (underneath is the cellar)